Sea Lion said:
Just so you know the thinking here, the water level check valve is fitted to locos without gauge glasses so you can obtain the correct water level when preparing your loco. On locos fitted with a gauge glass it is presumed owners will look at the water level in the glass when preparing their loco, and then continue looking at it from time to time as they need to top up every 10mins or so.
My Wrekin & Lawley each have both glass and level valve.
Some feedback, John, from experience.
I find the gauge glasses frequently difficult to read.
They often become grubby and can be air-locked. (other makes included here)
Dismantling to clean the glass often results in breakage, and loco out of service until repaired.
With the loco running at ground level, it's pretty awkward to see anyway.
Of course, running on a one-shot basis, it's all academic.
If I ever fit a top up system, things may change.